FinFETs could be used at 65-nm node says, TSMC CTO

SAN FRANCISCO  The FinFET, a transistor structure with a fin-like channel being touted as a way to scale silicon down to 10-nm gate lengths, could be used as early as the 65-nm process node, according to Calvin Chenming Hu, chief technology officer of Taiwan Semiconductor Manufacturing Co. Ltd.

The industry's failure to engineer a reliable high-k gate stack that limits leakage current for planar transistors could be one reason to go to three-dimensional structures, Hu said in an interview with SBN.

Hu, a distinguished researcher and academic prior to joining TSMC, helped develop prototypes of the FinFET in the 1990s.

The FinFET idea was picked up by Intel, AMD, IBM and TSMC, and the rivals have vied with each other to set the record for the smallest transistor. The approach is expected to scale to about a 10-nm gate length.

While they have been pushing to see how far the experimental FinFET could take semiconductors, Hu said FinFETs could enter commercial use with the 65-nm process technology, effectively the next process generation.

Advanced Micro Devices Inc. announced it has fabricated the world's smallest double-gated FinFETs with gates measuring just 10-nm in September 2002 before discussing them in a paper at the International Electron Devices Meeting.

Hu described a complementary pair of so-called Omega FinFET transistors on a 25-nm process at the same 2002 meeting. The 25-nm process node is scheduled for production in 2009.

And at the more recent International VLSI Symposium in Kyoto, Japan, Intel took the wraps off a tri-gate transistor structure for a manufacturing process technology with 30-nm critical dimensions could come into use in 2007. The vertical tri-gate transistor structure provides high drive current, low leakage current and a minimum of manufacturing difficulties, Intel said.

Hu said the need to optimize transistor performance and leakage current could drive the early use of FinFET devices.

"I think it [the FinFET] is going to be used, but not wholesale. There won't be a chip where you look in and every transistor is a FinFET. No, it will be used selectively where the performance requires it. I think it could come as early as the 65-nm node," Hu said.